/***************************************************************************/
/*                                                                         */
/*  ftsynth.c                                                              */
/*                                                                         */
/*    FreeType synthesizing code for emboldening and slanting (body).      */
/*                                                                         */
/*  Copyright 2000-2001, 2002, 2003, 2004, 2005, 2006, 2010 by             */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#include <ft2build.h>
#include FT_SYNTHESIS_H
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_OBJECTS_H
#include FT_OUTLINE_H
#include FT_BITMAP_H


/*************************************************************************/
/*                                                                       */
/* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
/* messages during execution.                                            */
/*                                                                       */
#undef  FT_COMPONENT
#define FT_COMPONENT trace_synth

/*************************************************************************/
/*************************************************************************/
/****                                                                 ****/
/****   EXPERIMENTAL OBLIQUING SUPPORT                                ****/
/****                                                                 ****/
/*************************************************************************/
/*************************************************************************/

/* documentation is in ftsynth.h */

FT_EXPORT_DEF(void)
FT_GlyphSlot_Oblique(FT_GlyphSlot slot)
{
    FT_Matrix transform;
    FT_Outline* outline = &slot->outline;


    /* only oblique outline glyphs */
    if (slot->format != FT_GLYPH_FORMAT_OUTLINE)
        return;

    /* we don't touch the advance width */

    /* For italic, simply apply a shear transform, with an angle */
    /* of about 12 degrees.                                      */

    transform.xx = 0x10000L;
    transform.yx = 0x00000L;

    transform.xy = 0x06000L;
    transform.yy = 0x10000L;

    FT_Outline_Transform(outline, &transform);
}


/*************************************************************************/
/*************************************************************************/
/****                                                                 ****/
/****   EXPERIMENTAL EMBOLDENING/OUTLINING SUPPORT                    ****/
/****                                                                 ****/
/*************************************************************************/
/*************************************************************************/


/* documentation is in ftsynth.h */

FT_EXPORT_DEF(void)
FT_GlyphSlot_Embolden(FT_GlyphSlot slot)
{
    FT_Library library = slot->library;
    FT_Face face = slot->face;
    FT_Error error;
    FT_Pos xstr, ystr;


    if (slot->format != FT_GLYPH_FORMAT_OUTLINE &&
        slot->format != FT_GLYPH_FORMAT_BITMAP)
        return;

    /* some reasonable strength */
    xstr = FT_MulFix(face->units_per_EM,
                     face->size->metrics.y_scale) / 24;
    ystr = xstr;

    if (slot->format == FT_GLYPH_FORMAT_OUTLINE)
    {
        /* ignore error */
        FT_Outline_Embolden(&slot->outline, xstr);

        /* this is more than enough for most glyphs; if you need accurate */
        /* values, you have to call FT_Outline_Get_CBox                   */
        xstr = xstr * 2;
        ystr = xstr;
    }
    else if (slot->format == FT_GLYPH_FORMAT_BITMAP)
    {
        /* round to full pixels */
        xstr &= ~63;
        if (xstr == 0)
            xstr = 1 << 6;
        ystr &= ~63;

        /*
         * XXX: overflow check for 16-bit system, for compatibility
         *      with FT_GlyphSlot_Embolden() since freetype-2.1.10.
         *      unfortunately, this function return no informations
         *      about the cause of error.
         */
        if ((ystr >> 6) > FT_INT_MAX || (ystr >> 6) < FT_INT_MIN)
        {
            FT_TRACE1(("FT_GlyphSlot_Embolden:"));
            FT_TRACE1(("too strong embolding parameter ystr=%d\n", ystr));
            return;
        }
        error = FT_GlyphSlot_Own_Bitmap(slot);
        if (error)
            return;

        error = FT_Bitmap_Embolden(library, &slot->bitmap, xstr, ystr);
        if (error)
            return;
    }

    if (slot->advance.x)
        slot->advance.x += xstr;

    if (slot->advance.y)
        slot->advance.y += ystr;

    slot->metrics.width += xstr;
    slot->metrics.height += ystr;
    slot->metrics.horiBearingY += ystr;
    slot->metrics.horiAdvance += xstr;
    slot->metrics.vertBearingX -= xstr / 2;
    slot->metrics.vertBearingY += ystr;
    slot->metrics.vertAdvance += ystr;

    /* XXX: 16-bit overflow case must be excluded before here */
    if (slot->format == FT_GLYPH_FORMAT_BITMAP)
        slot->bitmap_top += (FT_Int)(ystr >> 6);
}


/* END */